tajo-core/tajo-core-backend/src/main/java/org/apache/tajo/engine/planner/physical/HashJoinExec.java [127:184]:
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
      rightTuple = iterator.next();
      frameTuple.set(leftTuple, rightTuple); // evaluate a join condition on both tuples
      if (joinQual.eval(inSchema, frameTuple).isTrue()) { // if both tuples are joinable
        projector.eval(frameTuple, outTuple);
        found = true;
      }

      if (!iterator.hasNext()) { // no more right tuples for this hash key
        shouldGetLeftTuple = true;
      }

      if (found) {
        break;
      }
    }

    return outTuple;
  }

  protected void loadRightToHashTable() throws IOException {
    Tuple tuple;
    Tuple keyTuple;

    while ((tuple = rightChild.next()) != null) {
      keyTuple = new VTuple(joinKeyPairs.size());
      List<Tuple> newValue;
      for (int i = 0; i < rightKeyList.length; i++) {
        keyTuple.put(i, tuple.get(rightKeyList[i]));
      }

      if (tupleSlots.containsKey(keyTuple)) {
        newValue = tupleSlots.get(keyTuple);
        newValue.add(tuple);
        tupleSlots.put(keyTuple, newValue);
      } else {
        newValue = new ArrayList<Tuple>();
        newValue.add(tuple);
        tupleSlots.put(keyTuple, newValue);
      }
    }
    first = false;
  }

  @Override
  public void rescan() throws IOException {
    super.rescan();

    tupleSlots.clear();
    first = true;

    finished = false;
    iterator = null;
    shouldGetLeftTuple = true;
  }

  @Override
  public void close() throws IOException {
    super.close();
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -



tajo-core/tajo-core-backend/src/main/java/org/apache/tajo/engine/planner/physical/HashLeftOuterJoinExec.java [140:198]:
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
      rightTuple = iterator.next();
      frameTuple.set(leftTuple, rightTuple); // evaluate a join condition on both tuples
      if (joinQual.eval(inSchema, frameTuple).isTrue()) { // if both tuples are joinable
        projector.eval(frameTuple, outTuple);
        found = true;
      }

      if (!iterator.hasNext()) { // no more right tuples for this hash key
        shouldGetLeftTuple = true;
      }

      if (found) {
        break;
      }
    }

    return outTuple;
  }

  protected void loadRightToHashTable() throws IOException {
    Tuple tuple;
    Tuple keyTuple;

    while ((tuple = rightChild.next()) != null) {
      keyTuple = new VTuple(joinKeyPairs.size());
      List<Tuple> newValue;
      for (int i = 0; i < rightKeyList.length; i++) {
        keyTuple.put(i, tuple.get(rightKeyList[i]));
      }

      if (tupleSlots.containsKey(keyTuple)) {
        newValue = tupleSlots.get(keyTuple);
        newValue.add(tuple);
        tupleSlots.put(keyTuple, newValue);
      } else {
        newValue = new ArrayList<Tuple>();
        newValue.add(tuple);
        tupleSlots.put(keyTuple, newValue);
      }
    }
    first = false;
  }

  @Override
  public void rescan() throws IOException {
    super.rescan();

    tupleSlots.clear();
    first = true;

    finished = false;
    iterator = null;
    shouldGetLeftTuple = true;
  }


  @Override
  public void close() throws IOException {
    super.close();
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -